Sewing machine



June 19, 1956 w. H. D. LANGHEIN 2,750,907

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Wavre v afm United States Patent SEWING MACHINE Walter Heinrich Daniel Langhein, Hamburg-Volksdorf, Germany, assignor to Ingolf Felix Friedrich Emil Pauls, Basel, Switzerland Application September 4, i953, Serial N o. 378,656

Claims priority, application Germany September 8, 1952 5 Claims. (Cl. 112-220) The present invention relates to sewing machines.

More particularly, the present invention relates to sewing machines which are driven by electromagnets.

Conventional sewing machines of this type are usually provided with a pair of double solenoids'one of which n is connected to the needle bar for reciprocating the same and the other of which is connected to the shuttle. This arrangement is not very satisfactory, however, because it is almost impossible to properly time the operating of the two double solenoids so as to assure the best possible sequence of operations in the sewing process.

One of the objects of the present invention is to overcome these disadvantages by providing an electromagnetically driven sewing machine in which the desired sequence of operation of the various parts is assured. 30

Another object of the present invention is to arrange the sewing machine parts in such a way that they may all be operated from only one double solenoid.

A further object of the present invention is to provide a means for operating a thread tensioner where the seW- o ing machine is provided with only one double solenoid.

An additional object of the present invention is to provide a control means by which the operator may control the speed of operation of the sewing mauhine.

A still further object of the present invention is to provide a means for automatically or manually energizing the coils of the double solenoid.

Still another object of the present invention is to provide an apparatus capable of accomplishing all of the above objects while at the same time being made up of simply and ruggedly constructed parts which will have long life and give reliable service.

With the above objects in view, the present invention mainly consists of a sewing machine which includes a support having a pair of drive shafts turnably mounted thereon. A needle bar is operatively connected to one of the drive shafts to be operated thereby, and a thread tensioning means is operatively connected to the other of the drive shafts to be operated thereby. Also operatively connected to the other of the drive shafts are a shuttle means and a control means for controlling the speed of the sewing machine. A double solenoid is mounted on the support means and includes a pair of coils through and beyond which a single armature extends, this armature having one end operatively connected to the said one drive shaft and having an opposite end operatively connected to the other of the drive shafts to operate these drive shafts upon reciprocation of the armature during alternate energizing of the coils of the double solenoid.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 is a partly sectional, diagrammatic elevational view of a sewing machine constructed in accordance with the present invention;

Fig. 2 is a fragmentary, partly sectional elevational view of the double solenoid of the present invention and parts of the apparatus associated therewith;

Fig. 2a is a detailed, partly sectional view of the crank shown in the parts of the apparatus of Fig. 2;

Fig. 3 is a view of the structure of Fig. 2 as seen from the left side thereof;

Fig. 4 is a fragmentary, front elevational view of the needle bar and combination thread take-up and pull-off lever of the sewing machine;

Fig. 5 is a fragmentary, side view of the structure of Fig. 4 as seen from the left side thereof;

Fig. 6 is a fragmentary, partly sectional, elevational view of the structure of the sewing machine which is located beneath the needle and just to the right thereof;

Fig. 7 is a top plan View of the structure of Fig. 6 with the wall against which the cloth is placed removed to disclose the parts thereunder;

Fig. 8 is a view of the structure of Fig. 6 as seen from the left side thereof;

Fig. 9 is a sectional view taken along line IX-IX of Fig. 7 in the direction of the arrows;

Fig. 10 is a sectional View taken along line X-X of Fig. 7 in the direction of the arrows;

Fig. 1l is a sectional view taken along line XlXI of Fig. 7 in the direction of the arrows;

Figs. 10a and lla show the cams illustrated in Figs. l0 and l1 respectively, after having been rotated through 180;

Fig. l2 is a schematic wiring diagram illustrating the electrical connections of the sewing machine and diagrammatically showing the parts which actuate the several contacts and the like of the electrical circuit;

Fig. 13 is a fragmentary front view of one of the cams of the present invention; and

Figs. 14a to 14e are cross-sectional views of the cam shown in Fig. 3, taken respectively along the lines a-a, b-b, c-c, d-d, e-e, in the direction of the arrows.

Referring now to the drawings, and in particular to Figs. 1-3 thereof, it will be seen that the sewing machine of the invention is provided with a double solenoid having an upper coil 1 and a lower coil 2. A single armature extends through and beyond these coils which are ixedly mounted within the sewing machine housing as shown in Figs. l-3. A lever 4 is linked at 5 to the top end portion 3 of this armature (Fig. 3), and this lever 4 is iiXed to a shaft 8 which is turnably mounted in bearings 6 and 7 of the machine housing (Fig. 1). The lever 4 transmits a turning movement in opposite directions to the lever 8 during reciprocation of the armature of the double solenoid.

The shaft 3 is the drive shaft for the needle bar lil which is shown most clearly in Figs. 4 and 5. A tubular shaft 11 is located freely about the shaft 8 for free turning movement with respect thereto and is restrained against axial movement with respect to shaft by the collars l2 which are located at opposite ends of tubular shaft il. and fixed to the shaft A combination thread take-up and pull-off lever 13 is fixed to the tubular shaft ll as shown in Figs. 1, 4 and 5.

At the end of tubular shaft 11 opposite from the combination thread take-up and pull-off lever 13 there is a crank 14 which is fixed to member 1l and linked at i6 to an elongated rod means 15 made of two rod parts. The rod means l5 is slidably mounted in bearings 17 and 18 of the machine housing (Figs. 2 and 3) for reciprocating movement along its length. The two portions of rod means 15 are provided at their adjoining ends 19 and 20 with oppositely directed threads, as shown in Fig. 3, and a turn-buckle 21 threadedly engages these adjoining ends 19 and 26 of the rod portions 15 to adjust the length of the rod means 15. A coil spring 22 is located 'about the rod means 15 between bearing i7 and turnbuckle 2i to urge the rod means 15 in a downward direction, and the lower end of rod means 15 is fork-shaped at 23 to receive a roller 25 which is turnable on the pin 24 carried by the forked end 23 of the rod means 15.

The lower end 26 of the armature is linked at 27 to a connecting rod 23 which is connected to a crank 29 xed to and extending from a second drive shaft 32 which is turnably mounted on bearings 3i? and 3i located in the lower part of the machine housing (Fig. 1). Fig. 2a shows a detailed View of crank 29. Part of the portion of the connecting rod 2%, connected to crank 29, is shown cut away so that the crank 29 is visible. When the connecting rod 28 reciprocates, crank 29 causes the complete rotational movement of shaft 32. A cam 33 in the form of a disc eccentrically fixed to shaft 32 engages the roller 25 which is maintained against this cam 33 by the spring Z2. Thus, during reciprocation of the armature the shaft 32 is rotated through the crank drive 28, 29, and the eccentric disc 33 turns together with shaft 32. During a full rotation of the cam 33 the rod means 15 and tubular shaft 11 therewith are turned back and forth through a complete cycle so that the combination thread take-up and pull-od lever 1.3 pulls thread 36 from the spool 34, this thread 36 passing from the spool through the lever 13 and needle 35 in a manner well known in the art. Thus, the parts 11-25 together with the cam 33 form a thread take-up means for the sewing machine of the present invention.

The needle bar 1t) (Figs. 4 and 5) is mounted for reciprocating movement in bearings 37 and 38 of the machine housing 39. A clamp iii is fixed to the top end of the needle bar l@ and has opposite ears linked to a bar 41 extending between these ears. This bar d1 is linked at 42 to a forked lever 43 passing on opposite sides of the needle bar lil and being fixed to the drive shaft 8. Thus, when the armature reciprocates to turn the shaft 8 back and forth the latter transmits a vertical reciprocating movement to the needle bar it? through the members 43 and 41 so that in this way the needle 35 is operated.

As is shown in Figs. l and 2, a hand wheel 44- is fixed to the drive shaft 32 to permit the latter to be manually turned for manual operation of the machine when the tiow of current is turned ofi.

A gear 45 is fixed to the lower, second drive shaft 32, as shown in Figs. l and 7. The gear 45 meshes with a gear 46 which is keyed to a shaft i3 turnably mounted in the lower part 47 of the machine housing. A pair of elongated cams i9 and 5@ are located beside each other on the shaft 48 and fixed thereto.

The outer surface of each of these cams is provided with a portion which gradually decreases in its radial distance from the axis of shaft i8 in a direction from left to right, as viewed in Fig. 7, so that the arcuate operating length of these cams in planes transverse to shaft 48 gradually increases from right to left, as viewed in Fig. 7, and as is apparent from Figs. l and l1. These cams are diagrammatically illustrated in Fig. l2 where the operating surface of the cams is shown by the unshaded portions thereof. In other words, the operating surface of the cams 49 and Sti are located at a sufficient radial distance from the axis of shaft 43 to respectively maintain the contacts 51 and 52 closed, and the remaining shaded portion of the cams shown in Fig. 12 is located at a lesser radial distance from the axis of shaft 4S to open the contacts 51 and 52. Thus, as will be more fully described below, the sets of contacts i and 52 will be maintained closed for a greater portion of each rotation of these cams as these contacts are moved to the left as viewed in Figs. 7 and 12. The cams are opposed with respect to each other so as to be out of phase by approximately 180 so that the sets of contacts 51 and 52 are alternately closed and opened.

As is apparent from Figs. l0 and ll, as well as Figs. 7 and 12, the springy contacts 5l are located opposite the cam i9 and the springy contacts 52 are located opposite cam 5%, these contacts openings due to their own resiliency and becoming closed during engagement with the operating surface portion of their respective cams. Figs. 10a and lla show the cams 49 and Sti respectively, after having been rotated through 180. Fig. 13 is a detailed View of cam 5i) which is shown schematically in Fig. l. Figs. 14a to 14e are cross-sectional views at various positions along the length of cam Sti, taken respectively in the direction of the arrows a-a, b--b, c-c, d-d, e-e. The distance of the outer surface of the cam, from the shaft 48, at various portions along the length of the cam is clearly evident from Figs. 14a to 14e. Equivalent views of 'cam 49 would be similar to the above-mentioned cross-sectional views of cam 50. Both sets of contacts are mounted on a Ushaped carriage 53 the opposite legs of which are formed with bores through which the rods 54 and 55flixed to the machine housing extend, so that upon movement of the carriage 53 along these rods the sets of contacts 51 and 52 are respectively moved axially along the cams 49 and 50.

As is partly illustrated in Figs. 6 and 7 and most clearly shown in Figs. 9 and l2, a downwardly directed lever 56 serves to shift the carriage 53 along the rods 54 and 55, this lever 56 being pivotally mounted intermediate its length at 57 on the lower part 47 of the machine housing. The lever 56 is provided with a top fork-shaped end 58 in which a pin 59 fixed to the carriage 53 is located (Fig. 9). The lever 56 extends from the bottom of the housing and is accessible to the knee of the operator to be turned in a counterclocl;wise direction about pivot 57, as viewed in Fig. 12, so as to rnove the carriage 53 and contacts connected thereto to the left, as viewed in Figs. 7 and l2. As is schematically shown in Fig. 12, the lever Se' is maintained in its rest position by a spring 60 connected thereto and to the lower housing part 47, so that when the operator removes his or her knee from the lever 56 the spring 60 will automatically return lever 56 to the rest position shown in Fig. 12 where the lever abuts against a stop 6i lfixed to the housing part 47 (see also Fig. 6).

As is shown in Fig. 7, a shaft 5e Vis turnably mounted in bearings 62 63 of the machine housing and carries a ring shuttle 65 of a known construction. The ring shuttle 65 turns with the shaft 64, and the latter is turned by the bevel gear 66 fixed thereto and meshing with the bevel gear 67 which is xed to the shaft di? for rotation therewith. A side view of the ring shuttle arrangement is shown in Fig. 8.

A material feeding means for feeding the material to be stitched is provided on the sewing machine and is of a known'type which moves through a four-cornered endless path. Theshafts of the material feeding means are shown at 6% 73 in Fig. 9. The lever 74 of the parallelo-gram linka'gerhas a fork-shaped end 7S resting on a slide member having a convexly curved top surface '77 and a spring 7S urges the forked end 75 of lever 74 against the slide member 76. The shaft 63 is connected to a gear 81 meshing with a gear St) fixed to shaft 48 so that rotation 0f the latter rotates shaft 63 through the gear drive Si), 81. During operation the material feed ing means carries out its four-cornered motion and moves the material feeder 82 back and forth in a known way (Fig. 6). A device 83 for adiusting the stroke of the material feeder is illustrated in Fig. 9 and is of a known construction forming no part of the present invention. Shaft 68 carries an eccentric disc 79 which turns in a bore of member 76 to reciprocate the latter.

kThe electrical part of the apparatus is schematically illustrated vin Fig. l2. The machine may be operated with direct or alternating current and a re'ctiiier 84 is provided for this purpose. This rectifier is arranged so that the machine can be drivenwith direct current if desired. The switch for stopping and starting the machine includes the stationarypontact 85 and movable springy contact ,86. Contact 85 is connected to the rectifier, through the lead 87. The negative pole of the rectifier is connected through the lead 88 to the top and bottom coils 1 and 2 of the double solenoid. The positive pole 0f the rectifier is connected through the lead 89 to one of the contacts of each set of contacts 51 and 52. The other of the two contacts 51 is connected through the lead 90 to a contact 91 located opposite the arm 92 of a two-arm switch having the arms 92 and 93 which move together. The other of the contacts 52 is connected through the lead 94 with the contact 95 located opposite the second arm 93 of the switch 92, 93. This switch has the arm 92 connected to coil 1 and the arm 93 connected to coil 2, as shown in Fig. 12.

Three additional contacts 96-98 are provided in the circuit, the contacts 96 and 97 engaging each other in the rest position of the apparatus, shown in Fig. l2, and the contact 98 being fixed to the movable member 107 which alternately provides engagement between contacts 96 and 97 and contacts 96 and 98. The Contact 96 is connected through lead 89 with the positive pole of the rectifier 84, the contact 97 is connected through lead 100 to the contact 101 which engages switch arm 92 when it is in the dotted line position shown in Fig. l2, and the contact 98 is connected through lead 102 to the contact 103 which engages switch arm 93 when the latter is in the dotted line position shown in Fig. 12, the arms 92 and 93 moving together to engage either contacts 91 and 95, respectively, or contacts 100 and 103, respectively.

The lever 56 is linked at 104 to the rod 106 which actuates contact 86 and moves member 107 upon turning of the lever 56. The rod 106 is provided with insulation 105 on opposite sides of its connection at 104 to lever 56. The parts are dimensioned so that during the first part of the turning of lever 56 in the direction of the arrow at the bottom of Fig. 12 the rod 106 moves to the left to cause contact 86 to engage Contact 85 while the contacts 96-98 remain in the position shown in Fig. 12. During further turning of lever 56 and movement of rod 106 to the left, the contacts 85 and 86 remain closed while the member 107 gradually approaches contact 97 to engage the latter and move it from contact 96 while contact 98 moves toward contact 96 and engages the latter after contacts 96 and 97 are separated. Thus, alternate turning motion of lever 56 brings about engagementv of contact 96 alternately with contacts 97 and 93 while contacts 85 and 86 are in engagement with each other, and these latter contacts become separated only when the lever 56 is located near to the rest position shown in Fig. 12.

The above described electrical apparatus operates as follows:

The parts are shown in Fig. l2 in the position of normal sewing operation where switch arms 92, 93 respectively engage contacts 91 and 95. The operator moves his knee against lever 56 to turn the latter in the direction shown by the arrow at the lower part of Fig. 12. In this way the rod 106 is moved to the left to bring contact 86 against contact 85 so as to close the circuit and start the operation.

The current flows from the positive pole of rectifier 84 through the contacts 51 and lead 90 to the switch arm 92 and coil 1 back to the negative pole of the rectifier. The thus-energized coil 1 moves the armature upwardly and the shaft 8 is turned to move the needle bar 10 upwardly. Simultaneously the armature acts on the lov/er drive shaft 32 to rotate the same. The rotation of shaft 48 and cams 49 and 50 therewith causes the contacts 51 to become separated and the contacts 52 to engage each other.

Thus, the lower coil 2 is energized, after the coil 1 is deenergized, to move the armature in the opposite direction so as to continue the rotation of shaft 32 and to turn shaft 8 in the opposite direction so that in this way the armature reciprocates during alternate energizing of coils 1 and 2 to mn the machine. As the operator continues to turn the lever 56, the right leg of fork 58 engages pin 59 to move the carriage 53 and the sets of contacts 51 and 52 therewith to the left in the direction of the arrow shown in Fig. l2. As was mentioned above, the circumferential operating surface portions of the cams 49 and 50 increase in length from right to left, as shown by the unshaded portions of these cams in Fig. 12, so that as the carriage 53 moves to the left the sets of contacts are maintained closed during a constantly increasing portion of each revolution of the cams.

When the contacts 51 and 52 are located at the right hand end portions of the cams 49 and 50, respectively, a relatively short impulse is given to the coils so that the armature is positively moved during only a short part of its stroke and moves through the rest of its stroke due to inertia. As the sets of contacts 51 and 52 move to the left the electrical impulses are increased so that more electricity is consumed and the armature is positively moved during an increasing portion of its stroke and in this way the speed of movement of the armature and the machine parts connected thereto is increased. Thus, by pressing further against the lever 56 the operator can increase the speed of the machine until the carriage 53 abuts against the stop 108 shown in Fig. l2. As soon as the operator releases the lever 56, the latter is returned to the rest position shown in Fig. l2 by the spring 60 and just before the lever 56 arrives at the position shown in Fig. 12, the contact 86 moves away from contact to open the circuit and stop the machine.

There are times when the operator wishes to make individual stitches, and in order to do this the switch arms 92, 93 are moved from the contacts 91, 95 to the contacts 101, 103, as shown in dotted lines in Fig. l2. In this position of the apparatus the cams 19, 50 and the contacts associated therewith are disconnected from the coils 1 and 2 so that they have no eiiect on the operation.

In the dotted line position of the arms 92, 93 the current will flow from the positive pole of the rectifier 84 along the lead 99 to the central contact 96 and, when contacts 96 and 97 are in engagement with each other, from the contact 97 along the lead 100 to the top coil 1 and from the latter to the negative pole of the rectifier 84. As a result the armature is moved upwardly and the needle bar moves to its top position. All of these operations take place during the first part of the turningv of lever 56 in the direction of the arrow shown at the lower part of Fig. l2, since, as was described above, the contacts 85, 86 are closed during the first part of this movement and the contacts 96 and 97 remain closed for the next part of the turning movement of the lever 56.

During the further turning movement of this lever 56, however, the member 107 moves contact 97 away from contact 96 and contact 98 into engagement with contact 96, and with the parts in this position the current will flow along the line 102 to the lower coil 2 and from the latter to the negative pole of the rectifier, so that in this way the lower coil 2 is energized after the upper coil 1 is deenergized to cause the armature to move downwardly to move the machine through the next step in the sewing process. The operator need only allow the lever 56 to move back toward its rest position to again energize the top coil 1 after deenergizing the bottom coil 2, so that in this way the operator can, by moving lever 56 to the right and allowing .spring 60 to move the lever 56 back toward its rest position, alternately energize the coils 1 and 2 at will to carry out a slow, step by step stitching action.

The big advantage of this latter feature of the inven- 7 tion is that during this very slow step by step stitching process, the operator has both hands free to guide the material, and this is not the case with known machines where the operator must operate the machine with one hand so that only the other hand is available for guiding the material.

t will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of sewing machines differing from the types described above.

While the invention has been illustrated and described as embodied in electromagnetic sewing machines, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fuliy reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

l. A sewing machine comprising, in combination, support means; a double solenoid mounted on said support means for driving the various parts of the sewing machine and including a pair of coils and a single armature extending through and beyond said coils and being connected to the sewing machine parts for transmitting a drive thereto; and control means mounted on said support means and being operatively connected to said double solenoid for controlling the same, said control means including a shaft turnably mounted on said support means and being operatively connected to said armature to be rotated thereby, a pair of opposed cams fixed to said shaft for rotation therewith, and two sets of contacts respectively connected electrically to said coils and respectively being located on said support means opposite said cams to be alternately closed thereby so as to alternately energize said coils and reciprocate said armature.

2. A sewing machine comprising, in combination, support means; a double solenoid mounted on said support means for driving the various parts of the sewing machine and including a pair of coils and a single armature extending through and beyond said coils and being connected to the sewing machine parts for transmitting a drive thereto; and control means mounted on said support means and being operatively connected to said double solenoid for controlling the same, said control means including a shaft turnably mounted on said support means and being operatively connected to said armature to be rotated thereby, a pair of opposed cams fixed to said shaft for rotation therewith, each of said cams being elongated and extending along a substantial portion of length of said shaft and each of said cams having an arcuate operating surface portion which increases in width in one direction along the length of said shaft; a carriage mounted on said support means opposite said cams for movement in a direction parallel to said shaft; two sets of contacts mounted on said carriage respectively opposite said cams to be closed by engagement with said operating surface portions of said cams so that when said carriage is moved to move said sets of contacts in said one direction along said cams the arcuate length of the operating surface portion of the cams engaging said sets of contacts increases to provide a stronger impulse to said coils so as to reciprocate said armature at a faster rate, and operating means connected to said carriage and being accessible to the operator for moving carriage on said means for driving the various parts of the sewing machine and including a pair of coils and a single armature extending through and beyond said coils and being connected to the sewing machine parts for transmitting a drive thereto; control means mounted on said support means and being operatively connected to said double solenoid for controlling the same. said control means including a shaft turnably mounted on said support means and being operatively connected to said armature to be rotated thereby, a pair of opposed cams fixed to said shaft for rotation therewith, each of said cams being elongated and extending along a substantial portion of length 0f said shaft and each of said cams having an arcuate operating surface portion which increases in width in one direction along the length of said shaft; a carriage mounted on said support means opposite said cams for movement in a direction parrallel to said shaft; two sets of contacts mounted on said carriage respectively opposite said sams to be,

closed by engagement with said operating surface portions of said cams so that when said carriage is moved to move said sets of contacts in said one direction along said cams the arcuate length of the operating surface portion of the cams engaging said sets of contacts increases to provide a stronger impulse to said coils so as to reciprocate said armature at a faster rate, and operating means connected to said carriage and being accessible to the operator for moving carriage on said support means so as to thereby regulate the speed of operation of the sewing machine; an additional set of contacts electrically connected to said coils for alternately energizing same; switch means electrically connected to saidcoils between the latter and said sets of contacts for alternately connecting to said coils said first-mentioned sets of contacts or said additional set of contacts; and means for manually operating said additional set of contacts to alternately energize said coils at will.

4. A sewing machine comprising, in combination, support means; a double solenoid mounted on said support means for driving the various parts of the sewing machine and including a pair of coils and a single armature extending through and beyond said coils and being connected to the sewing machine parts for transmitting a drive thereto; control means mounted on said support means and being operatively connected to said double solenoid for controlling the same, said control means including a shaft turnably mounted on said support means and being operatively connected to said armature to be rotated thereby, a pair of opposed cams fixed to said shaft for rotations therewith, each of said cams being elongated and extending along a substantial portion of length of said shaft and each of said cams having ansarcuate operating surface portion which increases in width in one direction along the length of said shaft; a carriage mounted on said support means opposite said cams for movement in a direction parallel to said shaft; two sets of contacts mounted on said carriage respectively opposite said cams to be closed by engagement with said operating surface portions of said cams so that when said carriage is moved to move said sets of contacts in said one direction along said cams the arcuate length of the operating surface portion of the cams engaging said sets of contacts increases to provide a stronger impulse to said coils so as to reciprocate said armature at a faster rate, and operating means connected to said carriage and being accessible to the operator for moving carriage on said support means so as to thereby regulate the speed of operation of the sewing machine; an additional set of contacts electrically connected to said coils for alternately energizing same; switch means electrically connected to said coils between the latter and said sets of contacts for alternately connecting to said coils said first-mentioned sets of contacts or said additional set of contacts; and means for manually operating said additional set of contacts to alternately energize said coils at will, said means for manually operating said additional set of contacts being connected to said operating means to be operated thereby.

5. A sewing machine comprising, in combination, support means; a double solenoid mounted on said support means for driving the various parts of the sewing machine and including a pair of coils and a single armature extending through and beyond said coils and being connected to the sewing machine parts for transmitting a drive thereto; control means mounted on said support means and being operatively connected to said double solenoid for controlling the same, said control means including a shaft turnably mounted on said support means and being operatively connected to said armature to be rotated thereby, a pair of opposed cams ixed to said shaft for rotation therewith, and two sets of contacts respectively connected electrically to said coils and respectively being located on said support means opposite said cams to be alternately closed thereby so as to alternately energize said coils and reciprocate said armature; a pair of drive shafts turnably mounted on such support means and being operatively connected to said armature to be operated thereby; a needle bar operatively connected to one of said drive shafts to be operated thereby; combination thread take-up and pull-olf means operatively connected to the other of said drive shafts to be operated thereby; and shuttle means operatively connected to the other of said drive shafts to be operated thereby.

References Cited in the file of this patent UNITED STATES PATENTS 326,533 Wiggin Sept. 15, 1885 357,374 Darling et al Feb. 8, 1887 615,418 Wilkinson Dec. 6, 1898 1,196,160 Schooleld et al. Aug. 29, 1916 2,584,013 Hagquist Jan. 29, 1952 

